Turn on layers in the map when snapping for that layer is turned on

When selecting layers to snap to (e.g. using the measurement tools) the layers that have been selected for snapping are not automatically turned on and are therefore not visible in the map. Snapping to features that are not visible in the map is not very useful as a user cannot see to which features he/she would like to snap. It would therefore be a good enhancement to automatically turn on the layers in the layer list (and thus in the map) that are turned on for snapping.